1. Field of the Invention
Exemplary embodiments of the present invention relate to a method for manufacturing a thin film transistor array panel. In particular, exemplary embodiments of the present invention provide a method for manufacturing a thin film transistor array panel including a thin film transistor having thermal stability.
2. Discussion of the Background
Flat panel displays such as a liquid crystal display (LCD), an organic light emitting diode (OLED) display, an electrophoretic display, a plasma display, and the like include multiple pairs of electric field generating electrodes and an electro-optical active layer interposed therebetween.
The liquid crystal display includes a liquid crystal layer as the electro-optical active layer, and the organic light emitting display includes an organic light emitting layer as the electro-optical active layer.
Any one of a pair of electric field generating electrodes is generally connected to a switching element to receive an electrical signal, and the electro-optical active layer converts the electric signal into an optical signal to display an image.
The flat panel display may include a display panel having a thin film transistor. The thin film transistor array panel is patterned to have multiple electrodes and semiconductors, and masks are generally used in the patterning process.
On the other hand, the material of the semiconductor is an important factor in determining the characteristics of the thin film transistor.
The semiconductor is usually made of amorphous silicon. However, the charge mobility thereof is low such that there is a limit in manufacturing a high performance thin film transistor.
Also, when using polysilicon, the charge mobility is high such that manufacturing of the high performance thin film transistor is easy, however the cost is high and uniformity is low such that there is a limit in manufacturing a large-sized thin film transistor array panel.
Accordingly, a thin film transistor using an oxide semiconductor having high charge mobility and a high ON/OFF ratio of current compared with amorphous silicon and having a low cost and high uniformity compared with polysilicon has been researched.
For a characteristic of the channel layer of the oxide semiconductor, a high temperature heat treatment is performed after forming the source electrode and the drain electrode.
However, thermal stability between the metal material forming the source electrode and drain electrode, and the oxide semiconductor, is decreased such that the channel characteristic may be deteriorated.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.